Friction shock-absorbing device.



-T. H. EGGENSTEIN.

FRiCTION SHOCK ABSORBING DEVICE. APPLlCATiOH FILED NOV-13.1913,

Patented Nov. 16, 1915.

UNITED STATES PATENT mm THEODORE J. H. EGGENSTEIN, OF CHICAGO, ILLINOIS.

FRICTION SHOQK-ABSORBING DEVICE.

Specification of Letters'Patent. Pat ted Noir. 16, 1915.

Applicatior filed November 13,.19l3. Serial No. 800,738.

7 To all whom it mag "concern description of the same, such as will enableothers skilled in the art towhich it pertaiins to make and use the'same, reference being had to the accompanying drawings,

which forni a part of this specification.

My invention has for its object to produce a simple compact and powerful device for absorbing shocks without permitting an'objectionable recoil. 1

My invention is peculiarly adapted for ,--use in the draft gears of railway cars andin the drawing accompanying this speci fi'cation'I have illustrated the invention as embodied in a railway draft rigging. In the'accompanying drawing: Figure 1 is atop plan view of oneend of the draft sills of arailway car having associated therewith a; draft rigging arranged in accordance with a preferred form of my inivention; and- Fig. 2 is a section taken approximately on line 2-2Iof Fig. l.

so I I resent the draft sills of a railway car, while between and conne cting the draft sills togethervi' I I 1 3.5 v usualifyoke an elongated spiral, 6, rigidly Referring to the drawing-l and 2 rep- 3 "and 4 are separated stop, plates lying 5. is a draw bar having instead of the connected to the rear end thereof and pro- '-jecting through and guided by th'e stop -'fl; plates .3'-.and'4. If desired th'e' stop plates ,40

may .be -pro'vided with, suitable bushings, 7,

to form. bearings for the spiral and adaptedto' protect the stop plates from wear 1 .due to the inward and outward movement of v5i jthegspiral. Between the'stop plates and Ltan cefbetween the stop plates isfa drum, 8,

having-an eccentric opening extending lonoffajlength equal substantially to the disgitudinal-ly gtherethrough for receiving --the the two draft .spira'l'.;' the said opening beingparallel' with the, axis of the drum and being internally shaped inthe form of a spiral complemem' tary to-the spiral 6. Beneath the drum .is

I a transverse' plate,' 9, secured at it's ends-to 'andlhaving "its ,eIids attached to bolts, 1].

band overlying the fdrum drum and one of the stop plates, and be.-

and 12, which pass down beside the plate 9 or through a transverse slot, 13, in the plate. On the bolts' are strong springs, 14,

. engaging at their upper ends with the under side of the plate 9 and at their lower ends with nuts, 15, on-the bolts.

It will beseen that the'strap or band 10 is held against the drum under spring tension, the tension depending on the strength of the sprlngs and the distance to which the nuts 15 are screwed upon the bolts.

The parts are so disposed that when the coupler head is lying in its intermediateposition, that is in the position ordinarily 0ccupied by coupler heads when they are under neither a pulling nor a bufling strain,

posite sides of a vertical plane passing through the axis of the spiral and also through the axis of the drum; that is, the large side of the eccentric-being at the bottom.

- The operation is as follows: When a buffing strain comes upon the coupler, the spiral carried thereby is forced back, first carrying the druminto contact with the-rear stop plate 4 and then turning the drum in one direction or the other, for example, the

clockwise direction. As the drum turns it slides upon the bandor strap 10 so as to oppose the rearward movement of the coupler head with a frictional resistance. On account of the eccentricity of the drum the yoke like strap or band is lifted bodily as the drum turns and thus increases the tention on the springs: As the tension on'the springs increases the friction between the .drum and the strap or band also increases. Assuming the coupler to be connected to a corresponding coupler or another car andto be subjected to a pulling stress, the tendency vof the spiral 6 is to move forward or outward and, in so doing, itfirst \draws the drum into. contact with the front stop plate 3 and then begins to rotate the .'drum.in the opposite direction from that the drum is symmetrically disposed on opsimple said drum arranged parallel with and either direction absorb shocks imposed two directions tween the drum and the band or strap engaging the same; the friction increasing as pull increases. Furthermore, the initial resistance, that is the resistance to slight movements of the draw bar in maybe made comparatively small. so that the rigging will. not be so stifi as to make it unable effectively to absorb slight shocks. A very important advantage is that there is no recoil after a buffing or a pulling shock. Y

" It will thus parts cient shoclc absorber be seen that with a few strong I am able to produce, an eiiiwhich will effectively upon it in either of without having any objectionable recoil. It will also be seen that while my invention is particularly useful in connection with draft gears for railway cars it'is not limited to this single field but may used to advantage wherever it is desire td'have an efiicient shock absorbing cushion.

'1 claim: "1. In combination, a drum, a spiral extending into a complementary opening in at one side of the axis of the drum, a support fixedsrelative to the spiral in the transverse direction, a band passing over' said drum, and a spring between said band and said support.

2. In combination, a drum, a spiral extending into a one side of the axis of the drum. a friction member, and means for yieldably pressing said friction member against the periphery oi the drum.

partially surrounding 'the band, adjustable nuts complementary opening in said drum arranged parallel wvitli and at in combination, a frame containing two separated stop plates, and adapted toengage-at its end stop plates, a spiral extending through said stop plates and through said drum and aging. with a complementary the drum arranged at one side and parallel with the axis of the drum, a friction band partially surrounding the drum, able means between the ends of said band and the frame for pressingthe band against the drum. Y Y In combination, a frame containing two separated stop plates, a drum lying between and adapted to engage at its ends with said stop plates, a spiral extending through said stop plates and through said drum and engaging witha the drum arranged atone side and parallel with the axis of the drum, a friction band drum. screw threaded rods connected to the ends of the on said rods, and compression springs surrounding the rods and arranged between said nuts and said frame. 5. In combination, two members connected together by a spiral arranged parallel with and at one side of the axis of one of said members, and a yieldingly-pressed friction device engaging the periphery latter member. Y r In testimony whereof,

fication in the presence of two witnesses.

THEODORE J. H. EGGEXSTEIX. Witnesses i i WM; F. Fnnnnnwnsicn, RUTH E. ZETTERYALL.

a drum lying between s with said enopening in and yieldcomplementary opening in,

I sign this speciof the 

